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Circle / Sphere Converter

radius = r
diameter = 2 ⋅ r
perimeter = 2 ⋅ π ⋅ r
area of circle = π ⋅ r2
surface area of sphere = 4 ⋅ π ⋅ r2
volume of sphere
= 4/3 ⋅ π ⋅ r3

This is a converter for lengths, areas, and volumes of circles and spheres.

Type the value you want to convert into the respective field. Click on any free space of the window or on the "calculate"-button and read the result. Use the "reset" button to delete your calculation. The units change in correspondance to the input values (cm, cm2, cm3 or m, m2, m3 etc.).

Example: The radius of a sphere is 5 feet. What is its volume ? Type "5" into the field for the radius. Click on any free space of the window or on the "calculate"-button. Read the result for the volume of the sphere (523.6 cu ft).

- All results have been rounded to 5 significant digits.
- Large and small numbers are written exponentially. As example 2.3e5 = 2.3⋅105 = 230000 or 4.5e-5 = 4.5⋅10-5 = 0.000045.
- There is no warranty for the conversion. Cactus2000 is not responsible for damage of any kind caused by wrong results.
- Please send an email if you have suggestions or if you would like to see more conversions to be included.

- A collection of all Cactus2000-converters running offline may be ordered for a price of € 15.-. A test version is available for download for free.

© Bernd Krüger, 05.03.2001

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